diff --git a/compiler/rustc_codegen_ssa/src/codegen_attrs.rs b/compiler/rustc_codegen_ssa/src/codegen_attrs.rs index 5d7257b15c42e..15955170e8736 100644 --- a/compiler/rustc_codegen_ssa/src/codegen_attrs.rs +++ b/compiler/rustc_codegen_ssa/src/codegen_attrs.rs @@ -324,21 +324,22 @@ fn codegen_fn_attrs(tcx: TyCtxt<'_>, did: LocalDefId) -> CodegenFnAttrs { let linkage = Some(linkage_by_name(tcx, did, val.as_str())); if tcx.is_foreign_item(did) { codegen_fn_attrs.import_linkage = linkage; + + if tcx.is_mutable_static(did.into()) { + let mut diag = tcx.dcx().struct_span_err( + attr.span, + "extern mutable statics are not allowed with `#[linkage]`", + ); + diag.note( + "marking the extern static mutable would allow changing which symbol \ + the static references rather than make the target of the symbol \ + mutable", + ); + diag.emit(); + } } else { codegen_fn_attrs.linkage = linkage; } - if tcx.is_mutable_static(did.into()) { - let mut diag = tcx.dcx().struct_span_err( - attr.span, - "mutable statics are not allowed with `#[linkage]`", - ); - diag.note( - "making the static mutable would allow changing which symbol the \ - static references rather than make the target of the symbol \ - mutable", - ); - diag.emit(); - } } } sym::link_section => { diff --git a/tests/ui/linkage-attr/linkage-attr-mutable-static.rs b/tests/ui/linkage-attr/linkage-attr-mutable-static.rs index a7109c6d930bc..ed11947f59e74 100644 --- a/tests/ui/linkage-attr/linkage-attr-mutable-static.rs +++ b/tests/ui/linkage-attr/linkage-attr-mutable-static.rs @@ -4,12 +4,21 @@ #![feature(linkage)] fn main() { + #[rustfmt::skip] extern "C" { - #[linkage = "weak"] //~ ERROR mutable statics are not allowed with `#[linkage]` - static mut ABC: *const u8; + #[linkage = "extern_weak"] //~ ERROR extern mutable statics are not allowed with `#[linkage]` + static mut EXTERN_WEAK: *const u8; } unsafe { - assert_eq!(ABC as usize, 0); + assert_eq!(EXTERN_WEAK as usize, 0); + } + + // static mut is fine here as this is a definition rather than declaration. + #[linkage = "weak"] + static mut WEAK_DEF: u8 = 42; + + unsafe { + assert_eq!(WEAK_DEF, 0); } } diff --git a/tests/ui/linkage-attr/linkage-attr-mutable-static.stderr b/tests/ui/linkage-attr/linkage-attr-mutable-static.stderr index 4db41b6239382..ad9997690475b 100644 --- a/tests/ui/linkage-attr/linkage-attr-mutable-static.stderr +++ b/tests/ui/linkage-attr/linkage-attr-mutable-static.stderr @@ -1,10 +1,10 @@ -error: mutable statics are not allowed with `#[linkage]` - --> $DIR/linkage-attr-mutable-static.rs:8:9 +error: extern mutable statics are not allowed with `#[linkage]` + --> $DIR/linkage-attr-mutable-static.rs:9:9 | -LL | #[linkage = "weak"] - | ^^^^^^^^^^^^^^^^^^^ +LL | #[linkage = "extern_weak"] + | ^^^^^^^^^^^^^^^^^^^^^^^^^^ | - = note: making the static mutable would allow changing which symbol the static references rather than make the target of the symbol mutable + = note: marking the extern static mutable would allow changing which symbol the static references rather than make the target of the symbol mutable error: aborting due to 1 previous error